This invention relates to cutting machines such as grass cutting machines for sports or municipal usage. A typical ride-on grass cutting machine for such usage has multiple grass cutting units which may take the form, for example, of cutter reels or rotating cutters. There will typically be a centrally disposed cutting unit with left and right hand cutting units (or pairs of cutting units) mounted laterally so as to cut contiguous or slightly overlapping swathes as the machine is driven forward over the ground. Often, the left and right cutting units are liftable with respect to the chassis from a grass cutting position to a transport position in which the overall width of the machine is reduced.
In many cases, each cutting unit will incorporate a roller or other ground engaging element which serves in the cutting position to orientate the cutting blade or blades with respect to the ground so as to give the desired height of cut.
In many municipal areas and in some sports, it is a requirement to cut grass on ground that has substantial undulations. It is recognised that for the safety of the ride-on operator—and persons nearby—great care must be taken in design and in operation of the machine to ensure stability over the undulating ground.
It has been proposed on certain grass cutting machines and other utility vehicles to install an inclinometer and to provide a warning as a measured incline approaches a pre-set threshold or thresholds. It is recognised however that through inattentiveness—or because of competing demands—an operator may ignore warnings given to him.
Advantage is seen in providing an improved machine and method of operation in which steps are taken under certain conditions to improve the stability of the machine without reliance being placed on operator action.